A focused collection of 18 calculators, scores, and clinical references.
APACHE II score explanation and clinical context APACHE II is a severity scoring system developed to estimate risk of hospital mortality for patients admitted to intensive care. The score is the sum of an acute physiology score derived from the worst value in the first 24 hours for twelve physiologic variables plus points for age plus points for chronic health status. A higher total score indicates greater physiologi
APACHE IV calculation note APACHE IV is a validated severity scoring system published for hospital mortality assessment in critically ill adults. The original model uses many physiologic variables combined with spline terms and coefficients derived from a very large multicenter dataset. Reproducing the exact predicted mortality requires the original model coefficients or authorized software. This tool collects the da
Explanation and Clinical Context The Berlin Criteria provides a standardized method to diagnose acute respiratory distress syndrome based on the degree of hypoxemia, the requirement of positive end expiratory pressure, and the presence of bilateral opacities not fully explained by cardiac failure. The PaO2 FiO2 ratio defines the severity group. A ratio of three hundred or less with mandatory positive end expiratory p
Confusion Assessment Method for the Intensive Care Unit CAM ICU Delirium Assessment Tool Explanation and Clinical Context The CAM ICU is a structured bedside method used to identify delirium in critically ill patients including those who are unable to speak due to mechanical ventilation. The assessment consists of four clinical features. Feature one reflects acute onset or a fluctuating course which is determined thr
Charlson Comorbidity Index Explanation and Clinical Context Charlson Comorbidity Index is a widely used clinical scoring system that quantifies the burden of chronic disease and predicts the risk of mortality by assigning weights to specific comorbid conditions. It provides a structured method to estimate long term prognosis and helps clinicians stratify risk especially in hospitalized patients or those undergoing ma
Facial Expression Body Movements Select No movement or normal position Protective movement or slow cautious movement Restlessness or agitation Compliance with Ventilator Select Tolerating ventilator Coughing or mild resistance Asynchrony with ventilator Muscle Tension Select Relaxed Increased tone Rigid or very tense CPOT Pain Scale for Intubated Patients Explanation and Clinical Context The Critical Care Pain Observ
Inspired Oxygen Fraction FiO2 PaO2 arterial oxygen pressure mmHg PaCO2 arterial carbon dioxide pressure mmHg Atmospheric Pressure Patm mmHg Water Vapor Pressure PH2O mmHg Respiratory Quotient RQ Explanation and Clinical Context This calculator estimates the inspired oxygen fraction FiO2 together with the alveolar to arterial oxygen gradient which provides an assessment of gas exchange efficiency in the lungs. The alv
Minute Ventilation and Work of Breathing Explanation and Clinical Context Minute ventilation represents the total volume of air that a person moves in one minute and is calculated by multiplying tidal volume with respiratory rate. It reflects the global mechanical demand placed on the respiratory system. Normal resting minute ventilation is usually between five and eight liters per minute although it can increase sig
Modified Early Warning Score MEWS Explanation and Clinical Context Modified Early Warning Score is a bedside tool designed to identify patients at risk of clinical deterioration through a structured evaluation of vital signs and neurological status. MEWS incorporates respiratory rate heart rate systolic blood pressure temperature and level of consciousness. Each parameter is assigned points based on the degree of abn
NEWS Early Warning Score Explanation and Clinical Context The National Early Warning Score is a clinical scoring system designed to identify patients at risk of acute deterioration in hospital settings. The score integrates respiratory rate oxygen saturation the need for supplemental oxygen systolic blood pressure heart rate temperature and level of consciousness. Each variable contributes a weighted score based on s
FiO2 Mean Airway Pressure MAP PaO2 Oxygenation Index OI Explanation and Clinical Context Oxygenation Index is a validated measure used to quantify the severity of hypoxic respiratory failure and to evaluate the degree of ventilatory support required to maintain adequate oxygenation. The formula incorporates the fraction of inspired oxygen with mean airway pressure and arterial oxygen tension which allows clinicians t
Physiological Age Cardiac Signs Respiratory History Systolic Blood Pressure Pulse Rate Glasgow Coma Scale Hemoglobin White Cell Count Serum Urea Serum Sodium Serum Potassium Electrocardiogram Score Operative Severity Number of Procedures Blood Loss Peritoneal Contamination Presence of Malignancy POSSUM and P POSSUM Mortality Score Explanation and Clinical Context POSSUM Physiological and Operative Severity Score for
Respiratory RateEnter 1 if respiratory rate is 22 breaths per minute or higher otherwise enter 0 qSOFA Quick Sepsis Assessment Explanation and Clinical Context qSOFA is a rapid bedside tool designed to identify patients with suspected infection who are at increased risk for adverse outcomes such as prolonged intensive care stay and mortality. The score uses three simple clinical variables which are respiratory rate o
RASS Sedation Scale Explanation and Clinical Context The RASS sedation scale is a validated and widely used instrument to assess level of sedation and agitation in critical care settings. The scale spans from minus five to plus four and is oriented on the presence and degree of arousal and purposeful movement. A score of minus five indicates an unarousable state. Values from minus four to minus one denote progressive
RSBI Mechanical Ventilation Weaning Index Explanation and Clinical Context The rapid shallow breathing index known as RSBI is defined as the ratio of respiratory frequency to tidal volume in liters. It is calculated as respiratory rate divided by tidal volume in liters during spontaneous breathing conditions. RSBI measures the pattern of breathing and reflects the balance between respiratory drive and the ability of
Simplified Acute Physiology Score II SAPS II Explanation and Clinical Context The SAPS II score is a validated severity of illness classification intended to estimate risk of hospital death for adult patients admitted to intensive care units using the worst values collected in the first 24 hours after admission. The score aggregates points from 15 items including age type of admission heart rate systolic blood pressu
Temperature Celsius Heart Rate bpm Respiratory Rate PaCO2 mmHg White Blood Cell Count x10⁹ per L Band Form Percentage Explanation and Clinical Context SIRS describes a widespread inflammatory response of the body to internal or external stressors. It is defined by abnormalities in temperature heart rate respiratory rate PaCO2 and white blood cell count including increased immature neutrophil band forms. The criteria
SOFA Score for Organ Dysfunction Explanation and Clinical Context The Sequential Organ Failure Assessment score is a clinical tool that evaluates the severity of organ dysfunction across six major organ systems. These systems include respiration coagulation liver function cardiovascular status central nervous system and renal function. Each system receives a subscore between zero and four based on objective clinical